Automatic fastening machine

ABSTRACT

An automatic fastening machine characterized by a carriage carrying fastening guns over a workpiece on a table for fastening together the component parts of the workpiece; the fastening guns being pivotally mounted on the trailing side of the carriage so as to fire at predetermined points while the carriage is moving forward without jamming the carriage. Also disclosed are additional specific and advantageous structural features; such as, apparatus carried on the forward side of the carriage for automatically emplacing the component parts of the workpiece.

United States Patent [1113,576,236

[72] Inventor Troy J. Bunch 2,755,470 7/1956 Johnson 227/152X 18 Van Court, Hurst, Tex. 76053 3,018,482 1/1962 Voorhees 227/2 [21] Appl. N0. 784,569 3,026,519 3/1962 Johnson 227/2 [22] Filed Dec. 18, 1968 3,261,527 7/1966 Sterner 227/130X [45] Patented Apr. 27, 1971 3,381,870 5/1968 Haskins 227/3 3,443,513 5/1969 Jureit et a1. 227/152X [54] AUTOMATIC FASTENING MACHINE 4 Claims, 6 Drawing Figs.

[52] US. Cl 227/2, 227/99, 227/152 [51] Int. Cl. B27f7/06 [50] Field ofSearch 227/2, 3, 4, 45,48, 99,100,152,153,154

[56] References Cited UNITED STATES PATENTS 806,41 1 12/1905 lnwood et a1. 227/99X 2,080,462 5/ 1937 Cranston 227/45 2,111,081 3/1938 Taylor 227/45 Primary Examiner-Granville Y. Custer, Jr. Attorney-Wofiord and Felsman ABSTRACT: An automatic fastening machine characterized by a carriage carrying fastening guns over a workpiece on a table for fastening together the component parts of the work piece; the fastening guns being pivotally mounted on the trailing side of the carriage so as to fire at predetermined points while the carriage is moving forward without jamming the carriage. Also disclosed are additional specific and advantageous structural features; such as, apparatus carried on the forward side of the carriage for automatically emplacing the component parts of the workpiece.

AUTOMATIC FASTENING MACHINE BACKGROUND OF THE INVENTION slats; of the work piece.

Automatic nailing machines are known in the-prior art for nailing floors in a building. These automatic nailing machines often travel in a straight line across the floor automatically firing nails thereinto at preset intervals as a function of the setting of the machine itself. Such machines have not been amenable to automated processes for assembling workpieces.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an isometric view of a machine embodying the system of the invention.

FIG. 2 is a partial schematic and cross-sectional view of one aspect of an embodiment of the invention; specifically, the automatic positioning ofa component part of the workpiece.

FIG. 3 is a partial isometric view, partly schematic, of another aspect of one embodiment of the invention; specifically, one triggering mechanism which can effect actuation of the fastening guns.

FIG. 4 is a partial isometric view of another aspect of one embodiment of the invention; specifically, the air clutch drive mechanism employed in conjunction with electric motors and to effect movement along the longitudinal axis.

FIG. 5 is a partial isometric view of another aspect of one embodiment of the invention; specifically, the jigs and clamps holding the outer frame of the workpiece.

FIG. 6 is an isometric view of a mounting means employed in one embodiment of the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS The automatic fastening system of the invention comprises:

a. a table;

b. a carriage movable along the longitudinal axis of the table;

c. a fastening gun, fastening holding and feeding means attached to the gun, and a fastening driving means within the gun;

(I. actuator means for periodically actuating the driving means while the carriage is moving;

e. mounting means connecting the gun with the carriage, the mounting means providing sufficient movement of the guns away from the workpiece carried on the table that all parts of the gun and the fastener driving means clear all surfaces of the workpiece and prevent jamming.

FIG. 1 illustrates one embodiment of the invention in which the exterior frames, centerpiece, and slats are assembled beforethe rest of an innerspring mattress is formed thereupon. In FIG. 1, table 11 has a carriage 13 movable along the longitudinal axis of the table. To fasten together the outside frames, there is provided outer guns 15 and 17. While these outer guns may employ long staples, it has been found advantageous to employ nails such that the outer guns are automatic nailing guns. Outer guns have fastener holding and feeding means; such as, spring loaded nail magazines 19 and 21; attached thereto. Additional interior fastening guns 23, 25 and 27 are employed to fasten the slats 28 to outside frame 29 and centerpiece 31. Each of these interior fastening guns has attached a fastener holding and feeding means; such as, spring biased staple magazines 33, 35 and 37.

The fastening guns are mounted on carriage 13 by mounting means; such as pivotable holder 39 connected by pivotal shaft 41. In this way the fastening guns can be fired while the carriage is moving; and, since they are pivotably mounted on the carriage, will be moved away from the workpiece by recoil against the force of gravity such that all parts of the gun and the driving means, propelled from within the gun to drive home the fastening means, clear the surface of the workpiece and do not jam and adversely affect operation of the machine.

To drive the fastening means into the workpiece, a driving means within each gun is actuated or fired by actuator means. The actuator means may be a pneumatic signal from the keyboard integral with the table, as illustrated in FIG. 3 and described hereinafter with respect thereto; or any conventional signal source employed in this art.

In any event, the signal source is preprogrammed to effect an actuation signal for a group of guns at particular points as the carriage travels along the table.

To facilitate assembling the workpiece, slats 28 are placed in slat holder 43 with one end abutting aligner 45. The slats are then moved from the bottom of the stack and properly positioned by pins 47 and friction finger 49. Proper positioning insures proper fastening by fastening guns. A cross-sectional schematic of these essential elements is illustrated in FIG. 2. Therein, as the carriage and slat holder 43 mounted on the front of the carriage moves to the right down the longitudinal axis of the table, pin 47 prevents movement of the bottom slats 28'. Consequently, slat 23' drops near the base of pin 47 and the remainder of the slats 28 proceed down the table in their holder 43. To insure proper position of slat 28' frictional finger 49 on both sides of center fastening gun 25 juxtapose slat 28' with pin 47, which has been previously positioned in the proper hole for the particular configuration desired. As can be seen in FIG. 1, the pins, illustrated generically by pin 47, may be employed in a particular one of several holes 51 to effect any one of several possible configurations.

Any time the pins are changed to effect a new configuration, an actuator means must be recoded or made to operate in accord with a new program. FIG. 3 illustrates one embodiment in which an actuator means used to fire internal, or interior, fastening guns comprises a pneumatic signal effected by raising a spring mounted arm. The spring mounted arm is supported at its end on a wheel which tracks a given course down a keyboard which is integral with the table. Specifically, pneumatic switch 53 is caused to operate by raising lever arm 55. Lever arm 55 is raised by wheel 57 rolling over the raised head 59 of a hob-headed pin placed into one of the coded apertures 61 keyed into keyboard 63.

A duplicate actuator means is employed to fire outside fastener guns and is illustrated generically by actuator means 65 which tracks another lineal path along keyboard 63 and is fired in accordance with a different code.

The respective pneumatic switches 53 and 65 of the actuator means track along their respective lineal paths longitudinally of keyboard 63; and are positioned laterally on the two given linear tracks on keyboard 63 by rotation of adjusting screws and 137. As indicated hereinbefore, keyboard 63 extends lineally along the table 11 such that the hob-headed pins may be placed into the coded apertures 61 at predetermined locations. The raised heads of the pins thereafter effect firing of the respective outer fastening guns 15 and 17 and the interior fastening guns 23 and 25, and 27 as the carriage moves along table 11; and, consequently, mounting plates 139 and 141 move the switches 53 and 65 along the keyboard 63. Specifically, the plates 139 and 141 carry the respective pneumatic switches 53 and 65 along their respective linear paths such that the respective hob heads 59 of the hob-headed pins will raise wheel 57 and fire the respective fastening guns connected therewith. Adjusting screws 135 and 137 rotate freely in their mounting plates 139 and 141, rotatably held by U- shaped key 143. Mounting plates 139 and 141 are fixedly attached by any conventional means such as welding to carriage 13 and move in unison therewith. If desired, wheels (not shown may be installed on mounting plates 139 and 141 to afford a convenient adjustment in height and to track along a given path. Plate 139, plate 141, or both may be extended below keyboard 63 to further ensure that a given track is maintained each time carriage 13 traverses table 11.

The signal from actuator means 65 is fed to the outer guns 15 and 17 to fasten the corners of frame 29 together. Similarly, the signal from the other actuator means; specifically, pneumatic switch 53; is sent to the fastening guns 23 and 25 and 27 to fasten the slats to the outer frame and the centerpiece. Each of these signals is fed to the individual gun and actuates the driving means therewithin. In the embodiment illustrated in FIG. 1 the guns are fired pneumatically such that the actuator means effects operation of a poppet valve to fire the respective fastening guns and drive the fastener through the component parts and into another part of the workpiece. A signal from actuator means 65 is fed to the outer guns 15 and 17 through lines 67 and 69, whereas the signal from the pneumatic switch 53 is fed to inner fastening guns 23, 25 and 27 through lines 71, 73, and 75. Once the poppet valves are actuated the full pressure from the main header 77 is fed through lubricators 79 and 81, through power lines 83, 85, 87, 89, and 91 to fire the fastening guns. Consequently, the fastener driving means drives the fastening means into the workpiece. The

air affording power is fed through lubricators 79 and 81 containing a lubricant; such as, oil; which is entrained in the air and lubricates the driving means, poppet valve, and associated power equipment of the fastening guns.

Raising means; such as, pneumatic cylinders 93 and 95, having pistons inside; are provided to raise the carriage carrying the slat holder, fastening guns, and accessories before a return to the original end of the table from which a fastening cycle is started. Pnuematic cylinders 93 and 95 are fastened to carriage 13; are supported on a bridge 96 that moves horizontally with the carriage but is vertically fixed, and are connected with an air header for power. They are operated both automatically and by a manual switch.

To facilitate movement of the carriage in either direction along the longitudinal axis of the table, it has been found advantageous to employ pneumatic clutches such as illustrated in FIG. 4. Therein, electric motor 97 provides power via pulley 99, belt 101, and freely spinning power sheave 103. Pneumatic clutch 105 is employed, with its air cooled fins 107, to engage the traveling gears (not shown), and move carriage 13 riding along rail 109 on wheels; such as, wheel 111. The travelling gears, or pinions, running along a rack are conventional, do not form a part of this invention and need not be described herein. Hose 113 supplies air for activating the pneumatic clutch 105.

FIG. illustrates the way in which the outer frame is clamped into position before the slats are dropped thereinto and fastened. End jig 115 and side jig 117 are adjusted for the particular mattress size. The respective jigs may be bars, as illustrated in FIG. 5 or simply movable jig pins, as illustrated in .FIG. 1. Pins 47 are inserted in the apertures to effect the desired configuration. Thereafter, end clamps 119 and side clamps 121 are released by operation of their respective pneumatic cylinder, such as cylinder 123. The two bottom endpieces 125 are inserted into the jig then two bottom side pieces 127 and centerpiece 31 are inserted. Next the four top pieces, consisting of two endpieces 129 and two side pieces 131, are inserted and clamped into position by end clamp 119 and side clamps 121 through activation of their respective cylinders. The carriage with its precut slats, proceeds down the workpiece dropping and correctly emplacing the slats. Following on the trailing edge of the carriage, the fastening guns are fired to fasten all of the outer pieces of the frame together and to fasten the slats to bottom side pieces 127, and centerpiece 131. As soon as a complete traverse of the table by the carriage has been made, the pneumatic clutch effecting forward motion is disengaged; the other pneumatic clutch, on the opposite side and effecting reverse motion, is engaged; the pneumatic cylinders raising the carriage are activated; and the reverse cycle is made. Following the return to the original position of the carriage. end clamps 119 and side clamps 121 are released and a pneumatically powered cylinder operates an ejector to eject the workpiece from within jigs 115 and 117. The workpiece can be removed rapidly and a new framework introduced into the jig.

In operation, carriage 13 is positioned at end 133 of table 11 and outside frame 29 introduced into the jigs 115 and 117. Slats 28 are loaded into slat holders 43 with their ends flush against aligner 45. Pins 47 and the raised head pins 59 are positioned, respectively, in the correct apertures on table 11 and the correct coded apertures on keyboard 63 to effect the desired configuration. For example, there may be two groups of two raised head pins set in coded apertures in one track to actuate actuator means 65 and fire outer guns 15 and 17 twice in passing each corner. Similarly, raised head pins 59 may be employed in coded apertures in a second tract on keyboard 63 which are equivalent to the end and to each position to which a slat 28 is to be fastened. The raised heads raise lever arm 55 and fire pneumatic switch 53; consequently, firing fastening guns 23, 25, and 27 driving fasteners into the endpiece and into each of the respective slats.

Consequently, as the carriage begins its traverse forward on a fastening cycle, outer guns 15 and 17 drive two T-shaped nails into the corners of the outer frame, inner fastening guns 23, 25, and 27 drive their staples into the end and into sides and centerpieces to effect fastening. Furthermore, as carriage 13 travels down the table, the bottom slats 28' are raked from underneath the remaining slats and correctly positioned on the table by pins 47 and friction finger 49, fastening guns 23, 25, and 27 are fired by raising oflever arm 55 and firing pneumatic switch to fasten each respective slat to the sides and to the centerpiece. At the other end of the workpiece, outer guns are also signalled to fire their T-shaped nails into the corners and fastening guns 23, 25, and 27 drive home their staples to fasten the ends to, respectively, the sides and centerpiece.

In the event table 11 carries a second workpiece, the sequence of operations is repeated to secure the component parts of its together. Otherwise, pneumatic cylinders 93 and raise the fastening guns and accessories and the carriage returns to end 133. After the carriage 113 has returned to end 133, end clamps 119 and side clamps 121 are released, and the completed workpiece ejected from jigs and 117 by ejector means underneath the frame.

In order to be able to fire fastening guns while carriage 13 is moving, it is imperative that the fastening guns be mounted to carriage 13 such that the guns be moved away from the workpiece at the same time that the driving means of the gun drive home the fastening means. The guns must be moved away from the workpiece for a distance sufficient for all parts of the gun and the driving means to clear all surfaces of the workpiece to preventjamming. As indicated hereinbefore and as illustrated in FIG. 6, the guns may be mounted on the trailing side of carriage 13 in a pivotable holder 39 and pivotable about a pivotal shaft 41, and fulfill these requisites. Specifically, as the gun is fired, driving means drives the fastening means into the workpiece. In recoil to this force, the fastening guns are raised and are permitted to be raised by pivotable holder 39 rotating about pivotal shaft 41. The pivotal shaft 41 is, in turn, supported by mount fixed to carriage l3. Fastening guns may be retained in pivotable holder 39 by any suitable means; such as vise 147. Vise 147 is formed integrally with holder 39. .laws 151 fit closely about the fastening gun inserted therein and are clamped tightly by tightening threaded handle 153 on threaded bolt 155.

Any other mounting means may be employed which will allow sufficient recoil of the guns that all parts thereof clear all surfaces of the workpiece. For example, a supporting member, or guide, can be used as a reciprocal mounting on carriage 13 such that, upon driving the fastening means into the workpiece, the guns rebound by recoil for a distance sufficient for all parts of the gun to clear the workpiece. It is imperative, however, that the guns return to the correct position before they fire at the next succeeding proper time to fasten the next slat onto the sides and onto the centerpiece. Gravity alone may be sufiicient or return means; such as, a spring; may be employed to ensure that the guns return to the correct position before the next firing.

Although the invention has been described with respect to fastening together a framework to be employed in manufacturing a mattress, it is readily apparent that suitable jigs, pins, apertures, coded apertures and actuator means can be employed for fastening together component parts of any workpiece.

Moreover, although invention has been described with a high degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changesin the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.

1. An automatic fastening system comprising:

a. a table;

b. a carriage movable along the longitudinal axis of said table;

c. a fastening gun, fastener holding and feeding means attached to said gun, and a fastener driving means within said gun; I

d. actuator means for periodically actuating said driving means of said gun while said carriage is moving; and

e. mounting means comprising a supporting member carrying said gun and pivotally mounted on the side of said carriage that is the trailing side during a fastening cycle; whereby recoil of said gun provides sufficient movement of said gun against the force of gravity away from a workpiece carried on said table that all parts of said gun and said fastener driving means clear all surfaces of said workpiece and enable said gun to be fired while said carriage is moving without jamming.

2. The automatic fastening system of claim 1 wherein there is provided ahead of said gun holding means, dispensing means and positioning means for holding said component parts for said workpiece, for automatically and periodically distributing said component parts and for properly positioning said component parts of said workpiece before said gun is mattress; said holding means comprise vertical guides and an aligner mounted on the front of said carriage; said dispensing means comprise pins inserted into apertures in said table supporting said workpiece to displace the bottom slat from said holding means; and said positioning means comprises a friction finger to position said slat adjacent to said pin.

4. An automatic fastening system comprising:

a. a table;

b. jigs mounted on said table for conforming the outer frame of a workpiece;

c. pins and apertures within said jigs, said apertures being in the surface of said table, each said pins being positionable in one of a series of said apertures to effect a particular configuration of component parts of said workpiece;

d. clamps, ejectors and pneumatic cylinders, said clamps and said ejectors being powered by said pneumatic cylinders, connected ultimately with said table, and operable to respectively, clamp said outer frame of said workpiece within said jigs and to eject said workpiece from within said jigs;

e. a carriage and a longitudinal track, said carriage being movable along said longitudinal track, said longitudinal track being connected with said table;

f. motor, clutches, and wheels, said wheels being attached to said carriage and operable to transport it along said longitudinal track, said motor operable to supply power and one of said clutches being engageable to provide forward motion for a fastening cycle and the other of said clutches being engageable to provide reverse motion; g. component parts holder connected with said carriage,

located on the leading side thereof, and adapted to dispense component parts of said workpiece in response to urging from said pins during forward motion of said carriage; 4

h. friction fingers connected with said carriage and adapted to ensure said component parts are correctly positioned in juxtaposition with the respective ones of said pins;

i. fastening guns, fastener holding and feeding means attached to each said gun, and a fastener driving means within each said gun;

j. actuator means for periodically actuating said driving means while said carriage is moving;

. pivotal mounting means connecting said fastening guns with the side of said carriage that is the trailing side during said forward motion, said mounting means thereby providing for sufficient movement of said guns away from said workpiece that all the parts of said guns and said fastener driving means clear all surfaces of said workpiece when said guns are fired and prevent jamming; and

l. pneumatic cylinders for lifting said carriage before reversing motion to return said carriage to its original starting end. 

1. An automatic fastening system comprising: a. a table; b. a carriage movable along the longitudinal axis of said table; c. a fastening gun, fastener holding and feeding means attached to said gun, and a fastener driving means within said gun; d. actuator means for periodically actuating said driving means of said gun while said carriage is moving; and e. mounting means comprising a supporting member carrying said gun and pivotally mounted on the side of said carriage that is the trailing side during a fastening cycle; whereby recoil of said gun provides sufficient movement of said gun against the force of gravity away from a workpiece carried on said table that all parts of said gun and said fastener driving means clear all surfaces of said workpiece and enable said gun to be fired while said carriage is moving without jamming.
 2. The automatic fastening system of claim 1 wherein there is provided ahead of said gun holding means, dispensing means and positioning means for holding said component parts for said workpiece, for automatically and periodically distributing said coMponent parts and for properly positioning said component parts of said workpiece before said gun is fired.
 3. The automatic fastening system of claim 2 wherein said component parts are slats; said workpiece is a framework for a mattress; said holding means comprise vertical guides and an aligner mounted on the front of said carriage; said dispensing means comprise pins inserted into apertures in said table supporting said workpiece to displace the bottom slat from said holding means; and said positioning means comprises a friction finger to position said slat adjacent to said pin.
 4. An automatic fastening system comprising: a. a table; b. jigs mounted on said table for conforming the outer frame of a workpiece; c. pins and apertures within said jigs, said apertures being in the surface of said table, each said pins being positionable in one of a series of said apertures to effect a particular configuration of component parts of said workpiece; d. clamps, ejectors and pneumatic cylinders, said clamps and said ejectors being powered by said pneumatic cylinders, connected ultimately with said table, and operable to respectively, clamp said outer frame of said workpiece within said jigs and to eject said workpiece from within said jigs; e. a carriage and a longitudinal track, said carriage being movable along said longitudinal track, said longitudinal track being connected with said table; f. motor, clutches, and wheels, said wheels being attached to said carriage and operable to transport it along said longitudinal track, said motor operable to supply power and one of said clutches being engageable to provide forward motion for a fastening cycle and the other of said clutches being engageable to provide reverse motion; g. component parts holder connected with said carriage, located on the leading side thereof, and adapted to dispense component parts of said workpiece in response to urging from said pins during forward motion of said carriage; h. friction fingers connected with said carriage and adapted to ensure said component parts are correctly positioned in juxtaposition with the respective ones of said pins; i. fastening guns, fastener holding and feeding means attached to each said gun, and a fastener driving means within each said gun; j. actuator means for periodically actuating said driving means while said carriage is moving; k. pivotal mounting means connecting said fastening guns with the side of said carriage that is the trailing side during said forward motion, said mounting means thereby providing for sufficient movement of said guns away from said workpiece that all the parts of said guns and said fastener driving means clear all surfaces of said workpiece when said guns are fired and prevent jamming; and l. pneumatic cylinders for lifting said carriage before reversing motion to return said carriage to its original starting end. 